TWI545610B

TWI545610B - Lithography system and method of refracting

Info

Publication number: TWI545610B
Application number: TW100141406A
Authority: TW
Inventors: 賓艾利克山德亨卓克文森凡; 張艷霞; 剛莎拉馬利柏格隆德; 彼得克路特
Original assignee: 瑪波微影Ｉｐ公司
Priority date: 2010-11-13
Filing date: 2011-11-14
Publication date: 2016-08-11
Also published as: US20120145915A1; US9208989B2; WO2012062854A1; TW201234401A

Description

微影系統及折射之方法Lithography system and method of refraction

本發明關於一種成像系統且尤指一種帶電粒子多射束微影系統或檢查系統。The present invention relates to an imaging system and more particularly to a charged particle multi-beam lithography system or inspection system.

目前，大多數的商用微影系統使用遮罩作為一種機構來儲存及複製用於使諸如具有抗蝕劑塗層的晶圓之目標曝光的圖型資料。在無遮罩的微影系統中，帶電粒子射束被用來將圖型資料寫入到目標上。該等射束是例如藉由將其個別接通及切斷而經個別控制來產生所需的圖型。對於經設計操作在商用可接受產量之高解析度的微影系統，此類系統的尺寸、複雜度、與成本成為障礙。Currently, most commercial lithography systems use a mask as a mechanism to store and replicate pattern data for exposing a target such as a wafer with a resist coating. In a maskless lithography system, charged particle beams are used to write pattern data to the target. The beams are individually controlled to produce the desired pattern, for example by individually turning them on and off. The size, complexity, and cost of such systems are an obstacle to high resolution lithography systems that are designed to operate at commercially acceptable yields.

甚者，現存的帶電粒子束技術是適用於針對相當粗略的影像圖型化之微影系統，例如：達到90 nm及更高者的臨界尺度。然而，存在對於改良性能的增長需求。要達到例如22 nm之較小許多的臨界尺度而維持例如每小時在10與100個晶圓之間的充分晶圓產量是所期望。為了以持續減小的特徵尺寸來達到如此大的產量，必須增大在帶電粒子束中的電流。此增大的不想要效應是在於，歸因於較高電流，在帶電粒子之間的交互作用將增大而導致解析度的損失。Moreover, the existing charged particle beam technology is suitable for lithography systems that are relatively rough image-patterned, for example, critical dimensions up to 90 nm and above. However, there is an increasing demand for improved performance. It is desirable to achieve a much smaller critical dimension, such as 22 nm, while maintaining sufficient wafer throughput, for example between 10 and 100 wafers per hour. In order to achieve such a large yield with a continuously decreasing feature size, it is necessary to increase the current in the charged particle beam. The unwanted unwanted effect is that, due to the higher current, the interaction between charged particles will increase resulting in a loss of resolution.

為了抵消在帶電粒子之間的交互作用，必須提高系統的場大小，即：在一個週期所曝光的面積大小。以此方式，交互作用被降低。In order to counteract the interaction between charged particles, the field size of the system must be increased, ie the size of the area exposed in one cycle. In this way, the interaction is reduced.

對於此類系統要提供圖型的準確寫入諸如晶圓的目標上，本質的是，帶電粒子束被投射到有非常受控制特性的目標上。在投射系統中的誤差將使得經投射的影像劣化。在整個帶電粒子光學系統中，諸多的因素促成在圖型中的誤差。For such systems to provide accurate mapping of patterns to targets such as wafers, it is essential that the charged particle beam is projected onto a target with very controlled characteristics. Errors in the projection system will degrade the projected image. In the entire charged particle optical system, a number of factors contribute to errors in the pattern.

一個此類主要的促成因素是所謂的準直器，其作用為從發自帶電粒子源的發散束而產生實質平行的帶電粒子束。One such major contributing factor is the so-called collimator, which acts to produce a substantially parallel bundle of charged particles from a diverging beam originating from a charged particle source.

已知系統經常應用靜電透鏡，其包含多個電極來用於帶電粒子束的聚焦或準直化。關於此種透鏡的已知問題是在於其因透鏡的電極所引入的球面與色像差而更糟，降低經投射影像的品質。當提高曝光的場大小，此等像差反而增大。Known systems often employ electrostatic lenses that contain multiple electrodes for focusing or collimating the charged particle beam. A known problem with such a lens is that it is worse due to the spherical surface and chromatic aberration introduced by the electrodes of the lens, reducing the quality of the projected image. When the field size of the exposure is increased, these aberrations increase instead.

由於此類的已知透鏡典型為考慮到像差或束均勻度的一些控制，然而此等者無法提供對於高檔的帶電粒子微影所需程度的要求。已知設計無法可靠且成本有效地提供在臨界尺度的降低，如對於微影工業的未來發展準則所需。為了維持商用可行的產量，在臨界尺度的降低典型為需要其可經沉積在目標上的帶電粒子的增大。達成此舉的一個方式是大量增加所使用射束的數目。此對於已知設計而言為不可能。Since known lenses of this type are typically some control that takes into account aberrations or beam uniformity, these do not provide the required degree of lithography for high-grade charged particles. Known designs are not able to provide a reduction in critical dimensions reliably and cost effectively, as required for future development guidelines for the lithography industry. In order to maintain commercially viable yields, the reduction in critical dimensions is typically an increase in charged particles that are required to be deposited on the target. One way to achieve this is to increase the number of beams used in large numbers. This is not possible for known designs.

在專利WO 2007/013802號所揭示的一個此類系統包含其與帶電粒子源一起在真空中操作的帶電粒子柱，其包括帶電粒子取出機構、用於從取出的帶電粒子來產生複數個平行射束的機構、以及包含電極的複數個靜電透鏡結構。靜電透鏡結構尤其是作為使射束聚焦及熄滅之目的。在此系統中的熄滅是藉由將此類通常聚焦的帶電粒子束中的一或多者偏轉所實現來阻止粒子束或多個射束到達諸如晶圓的目標。為了實現在基於電腦的影像圖型之目標上的投射的最終部分，未經熄滅的射束是在此類靜電透鏡中的最後一組而朝所謂的寫入方向偏轉，因而經掃描在目標表面上，作為部分的目標成像過程。One such system disclosed in the patent WO 2007/013802 comprises a charged particle column operating in a vacuum with a charged particle source, comprising a charged particle extraction mechanism for generating a plurality of parallel shots from the extracted charged particles The mechanism of the bundle, and a plurality of electrostatic lens structures including the electrodes. The electrostatic lens structure is especially intended to focus and extinguish the beam. Extinction in this system is accomplished by deflecting one or more of such normally focused charged particle beams to prevent the particle beam or beams from reaching a target such as a wafer. In order to achieve the final part of the projection on the target of the computer-based image pattern, the unextinguished beam is deflected in the so-called writing direction in the last group of such electrostatic lenses and thus scanned over the target surface On, as part of the target imaging process.

另一種帶電粒子系統是從專利WO 2010/037832號中為已知，其關於一種包含靜電透鏡或透鏡陣列的帶電粒子微影系統，描述投射場的細分成為包含其用於讓帶電粒子束通過的隙縫、不用於讓束通過的隙縫、以及不包含隙縫而是為了機械強度所包括的條狀物之區域。Another charged particle system is known from the patent WO 2010/037832, which relates to a charged particle lithography system comprising an electrostatic lens or a lens array, describing the subdivision of the projection field to include it for passing a charged particle beam. The slit, the slit that is not used to pass the bundle, and the region that does not contain the slit but is included for the mechanical strength.

因此需要一種解決方式，其可經規模放大到所需大量的平行帶電粒子束而使像差降低到適用於高檔的帶電粒子微影的程度。There is therefore a need for a solution that scales up to a large number of parallel charged particle beams as needed to reduce aberrations to the extent that it is suitable for high-grade charged particle lithography.

本發明之一個目標是要克服如在已知系統中所發現的問題。此目標是藉由提出一種帶電粒子系統來達成，該種帶電粒子系統包括一種用於將圖型轉移到諸如晶圓的目標表面上之微影系統，其包含一種用於將圖型轉移到目標表面上之帶電粒子曝光工具，該曝光工具包含其適用於產生發散的帶電粒子束之帶電粒子源及其用於使該發散的帶電粒子束折射之收斂機構，收斂機構包含第一電極與其包含複數個隙縫的隙縫陣列元件，其經包括以形成第二電極，適用於在第一電極與第二電極之間建立電場。It is an object of the present invention to overcome the problems found in known systems. This object is achieved by proposing a charged particle system comprising a lithography system for transferring a pattern onto a target surface such as a wafer, the method comprising a method for transferring a pattern to a target a charged particle exposure tool on a surface, the exposure tool comprising a charged particle source adapted to generate a diverging charged particle beam and a convergence mechanism for refracting the diverged charged particle beam, the convergence mechanism comprising a first electrode and a plurality thereof A slotted slot array element that is included to form a second electrode adapted to establish an electric field between the first electrode and the second electrode.

藉由在第一電極與第二電極(其經實施為隙縫陣列)之間施加電場，要顯著降低由電子束之準直化所引入的像差是成為可能的。藉由讓來自第一電極的電場以特定電荷而終止在置放於束中的導線上，可達成的像差降低程度是比否則由收斂機構的電壓與幾何性之僅有調整所將為可能者而較高許多。此接著允許曝光的場大小被提高到所需程度。By applying an electric field between the first electrode and the second electrode, which is implemented as a slot array, it is possible to significantly reduce the aberration introduced by the collimation of the electron beam. By terminating the electric field from the first electrode with a specific charge and terminating on the wire placed in the beam, the degree of aberration reduction that can be achieved is more likely than otherwise by the adjustment of the voltage and geometry of the convergence mechanism. And much higher. This in turn allows the field size of the exposure to be increased to the desired level.

在再一個實施例中，電場是加速電場。In still another embodiment, the electric field is an accelerating electric field.

在再一個實施例中，加速電場是藉由將第一電極以關於第二電極的相對較低電位來配置所建立。In still another embodiment, the accelerating electric field is established by configuring the first electrode at a relatively lower potential with respect to the second electrode.

在再一個實施例中，第二電極是被細分成為交替的無隙縫區域與複數個隙縫為存在其處的區域。由於隙縫的存在，射束可隨著其能通過隙縫陣列而產生。非束區域是無隙縫的區域。結果，並無射束是在此類的區域中產生。In still another embodiment, the second electrode is subdivided into alternating gapless regions and a plurality of slits are regions present therein. Due to the presence of the slit, the beam can be generated as it can pass through the array of slits. The non-beam area is the area without gaps. As a result, no beam is produced in such a region.

在再一個實施例中，無隙縫區域是備有一或多個未貫穿孔。以此方式，在第一與第二電極之間的電場是在交替的束與非束區域上(甚至在該等區域的邊緣處)維持均勻。In still another embodiment, the gapless region is provided with one or more non-through holes. In this way, the electric field between the first and second electrodes is maintained uniform over alternating beam and non-beam regions, even at the edges of the regions.

在再一個實施例中，無隙縫區域被包括在經升高在無隙縫區域之上方的高度處。以此方式，再者，在第一與第二電極之間的電場是在交替的束與非束區域上維持均勻。In still another embodiment, the gapless region is included at a height that is raised above the gapless region. In this way, again, the electric field between the first and second electrodes is maintained uniform over the alternating beam and non-beam regions.

在再一個實施例中，無隙縫區域是備有用於冷卻媒體的導管。在非束區域內的冷卻之使用可改良曝光工具的性能。In still another embodiment, the gapless region is provided with a conduit for cooling the medium. The use of cooling in the non-beam region improves the performance of the exposure tool.

在再一個實施例中，隙縫是被包括自面對該源的表面所凹陷處。In still another embodiment, the slit is included as being recessed from the surface facing the source.

在再一個實施例中，該等隙縫是被包括在無電場的高度。電場將“脹大”到凹陷部而改變電場的均勻性。In still another embodiment, the slots are included at a height that is free of electric fields. The electric field will "swell" to the depressions to change the uniformity of the electric field.

在再一個實施例中，經凹陷的隙縫是在電場的影響下而形成負透鏡。In still another embodiment, the recessed slits form a negative lens under the influence of an electric field.

在再一個實施例中，第一電極的填充因數是大於50%。In still another embodiment, the fill factor of the first electrode is greater than 50%.

在再一個實施例中，在第二電極中的隙縫的填充因數是大於50%。In still another embodiment, the fill factor of the slit in the second electrode is greater than 50%.

在再一個實施例中，收斂機構更包含以聚焦鏡組(Einzel lens)之形式的至少三個附加電極，其可用於使帶電粒子束為準直。In still another embodiment, the convergence mechanism further comprises at least three additional electrodes in the form of an Einzel lens that can be used to collimate the charged particle beam.

在再一個實施例中，電極具有面對帶電粒子束的曲面，其具有在30與70 mm之間的曲率半徑，確保並無電氣崩潰發生。In still another embodiment, the electrode has a curved surface facing the charged particle beam having a radius of curvature between 30 and 70 mm to ensure that no electrical collapse occurs.

已經注意到的是，並非在所有情形中的像差是經降低到所需的位準。在再一個實施例中，隙縫陣列元件是備有彎曲表面。以此方式，由電極所造成的像差可被降低。It has been noted that not all aberrations are reduced to the required level. In still another embodiment, the slot array element is provided with a curved surface. In this way, the aberration caused by the electrodes can be reduced.

在再一個實施例中，該彎曲表面是被包括在面對源側。In still another embodiment, the curved surface is included on the source side.

在再一個實施例中，彎曲表面是根據置中在環繞系統光軸的餘弦函數所成形。In still another embodiment, the curved surface is shaped according to a cosine function centered on the optical axis of the surrounding system.

在再一個實施例中，彎曲表面的周長是實質大於彎曲表面的高度。In still another embodiment, the perimeter of the curved surface is substantially greater than the height of the curved surface.

在再一個實施例中，彎曲表面的半徑是大於帶電粒子束的半徑。In still another embodiment, the radius of the curved surface is greater than the radius of the charged particle beam.

在再一個實施例中，隙縫具有在面對源側的第一直徑d1以及在面對目標側的第二直徑d2，且其中d1是小於d2。In still another embodiment, the slit has a first diameter d1 facing the source side and a second diameter d2 facing the target side, and wherein d1 is less than d2.

在再一個實施例中，收斂機構是以單一元件準直透鏡之形式的第一電極所組成。In still another embodiment, the convergence mechanism is comprised of a first electrode in the form of a single element collimating lens.

在再一個實施例中，第一電極包含第一凸部分與第二凸部分，第一部分具有第一橫截面，第二部分具有第二橫截面，其中第二橫截面的平均直徑是大於第一橫截面的平均直徑。In still another embodiment, the first electrode includes a first convex portion and a second convex portion, the first portion has a first cross section, and the second portion has a second cross section, wherein the average diameter of the second cross section is greater than the first The average diameter of the cross section.

在再一個實施例中，第一部分的高度是大於第二部分的高度。In still another embodiment, the height of the first portion is greater than the height of the second portion.

在再一個實施例中，第一部分與第二部分是使用磨圓的接頭來接合。In still another embodiment, the first portion and the second portion are joined using a rounded joint.

在再一個實施例中，第一電極是由極板材料所作成。In still another embodiment, the first electrode is made of a plate material.

本發明還包含一種使發散的帶電粒子束折射之方法，該種方法包含：藉由帶電粒子源來提供發散的帶電粒子束；藉由收斂機構來使該發散的帶電粒子束進一步折射，收斂機構包含第一電極與第二電極，第二電極是採取隙縫陣列的形式；在第一電極與第二電極之間建立加速電場；且，從經折射的帶電粒子束來產生複數個實質平行的帶電粒子射束。The present invention also encompasses a method of refracting a diverging charged particle beam, the method comprising: providing a diverging charged particle beam by a charged particle source; further refracting the diverging charged particle beam by a convergence mechanism, a convergence mechanism The first electrode and the second electrode are included, the second electrode is in the form of an array of slits; an accelerating electric field is established between the first electrode and the second electrode; and a plurality of substantially parallel charges are generated from the refracted charged particle beam Particle beam.

本發明更包含一種使用在帶電粒子微影系統中的隙縫陣列元件，該種元件包含複數個隙縫且被細分成為交替的無隙縫區域與該複數個隙縫為存在其處的區域。該種隙縫陣列元件可具有針對帶電粒子系統的隙縫陣列之上述特徵中的任一者。The invention further encompasses a slot array element for use in a charged particle lithography system, the element comprising a plurality of slits and subdivided into alternating gapless regions and the plurality of slits being regions present therein. The slot array element can have any of the above features for a slot array of charged particle systems.

本發明更包含一種帶電粒子束產生器，其包含：帶電粒子源，其適用於產生發散的帶電粒子束；收斂機構，其用於使該發散的帶電粒子束折射，收斂機構包含第一電極；及，隙縫陣列元件，其形成第二電極；其中該種系統是適用於在第一電極與第二電極之間建立電場。該等電極、收斂機構、及隙縫陣列元件可具有針對帶電粒子系統的此等元件之上述特徵中的任一者。The invention further comprises a charged particle beam generator comprising: a charged particle source adapted to generate a diverging charged particle beam; a convergence mechanism for refracting the diverging charged particle beam, the convergence mechanism comprising a first electrode; And a slit array element that forms a second electrode; wherein the system is adapted to establish an electric field between the first electrode and the second electrode. The electrodes, convergence mechanisms, and slot array elements can have any of the above features for such elements of a charged particle system.

本發明更包含一種方法，其中加速電場是藉由將第一電極置放在相較於第二電極的相對較低電位所建立。The invention further comprises a method wherein the accelerating electric field is established by placing the first electrode at a relatively lower potential than the second electrode.

下文是本發明的某些實施例的描述，其僅為舉例而言且參考圖式。圖1示意顯示一種用於將影像(尤指控制系統提供影像)投射到目標上的帶電粒子系統1。該種系統包括部分的本發明為特別關於其的晶圓台構件。在此設計中，帶電粒子系統包含控制系統2、經安裝在底座8之上的真空室3，其容納有帶電粒子柱4、計量框架6與目標定位系統9-13。目標9將通常為晶圓，其備有基板表面上的帶電粒子敏感層。目標9被置放在晶圓台10的頂部上，晶圓台10接著被置放在夾頭12與長衝程驅動器13之上。測量系統11被連接到計量框架6，且提供晶圓台10與計量框架6的相對定位測量。計量框架6典型為相當高的質量且由振動隔離器7所懸吊，振動隔離器7是例如由彈簧元件所實施以使干擾減輕。電子光學柱4使用投射器5來實行最終的投射。投射器5包含靜電或電磁投射透鏡的系統，用於將在帶電粒子柱中所產生的帶電粒子束投射到目標上。在如所描繪的較佳實施例中，投射透鏡系統包含靜電帶電粒子透鏡的陣列。為了支承且固定整個投射器，透鏡系統被納入在承載框架中。 The following is a description of some embodiments of the invention, which are by way of example only and reference to the drawings. Figure 1 shows schematically a charged particle system 1 for projecting an image, in particular an image provided by a control system, onto a target. Such a system includes a portion of the present invention as a wafer table member particularly relevant thereto. In this design, the charged particle system comprises a control system 2, a vacuum chamber 3 mounted above the base 8, which houses a charged particle column 4, a metrology frame 6 and a target positioning system 9-13. Target 9 will typically be a wafer that is provided with a charged particle sensitive layer on the surface of the substrate. The target 9 is placed on top of the wafer table 10, which is then placed over the chuck 12 and the long stroke driver 13. The measurement system 11 is connected to the metrology frame 6 and provides relative positioning measurements of the wafer table 10 and the metrology frame 6. The metering frame 6 is typically of relatively high quality and is suspended by a vibration isolator 7, which is implemented, for example, by a spring element to mitigate interference. The electron optical column 4 uses the projector 5 to perform the final projection. The projector 5 comprises a system of electrostatic or electromagnetic projection lenses for projecting a beam of charged particles produced in a charged particle column onto a target. In the preferred embodiment as depicted, the projection lens system comprises an array of electrostatically charged particle lenses. In order to support and secure the entire projector, the lens system is incorporated into the carrier frame.

為了達到在大運動範圍的所需準確度，晶圓定位系統典型包含：長衝程驅動器13，其用於將晶圓台朝掃描方向及垂直於掃描方向移動越過相當大的距離；及，短衝程構件12，其用於準確實行目標9的定位且用於修正干擾。關於計量框架6之晶圓台的相對定位是由測量系統11所測量。目標9被夾緊到晶圓台10之上以確保目標9在帶電粒子束到目標上之投射期間的固定。 In order to achieve the required accuracy in a large range of motion, a wafer positioning system typically includes a long stroke driver 13 for moving the wafer table in a scanning direction and perpendicular to the scanning direction over a substantial distance; and, a short stroke A member 12 for accurately performing the positioning of the target 9 and for correcting interference. The relative positioning of the wafer table with respect to the metrology frame 6 is measured by the measurement system 11. The target 9 is clamped onto the wafer table 10 to ensure the fixation of the target 9 during projection of the charged particle beam onto the target.

圖2顯示一種帶電粒子柱4的示意代表圖。在此系統中，帶電粒子源17產生帶電粒子束18。帶電粒子束隨後通過準直透鏡19，其用於使得帶電粒子束為準直。其次，經準直後的帶電粒子束是由隙縫陣列21所變換成為複數個射束22，在此實例中，隙縫陣列21包含具有通孔的平板，其阻隔部分的準直束且允許射束22通過。此隙縫陣列是典型為離該準直透鏡的一段顯著距離而位在無場區域中，如可在圖2所看出。 Figure 2 shows a schematic representation of a charged particle column 4. In this system, charged particle source 17 produces charged particle beam 18. The charged particle beam then passes through a collimating lens 19 which is used to collimate the charged particle beam. Second, the collimated charged particle beam is transformed by the slot array 21 into a plurality of beams 22. In this example, the slot array 21 includes a plate having through holes that block portions of the collimated beam and allow the beam 22 by. The slot array is typically located at a significant distance from the collimating lens and in the field free region, as can be seen in FIG.

射束22經投射在熄滅機構23上，在此實例中，熄滅機構23包含其備有偏轉機構的隙縫陣列。熄滅機構23是能夠將個別選擇的射束24偏轉到其與熄滅機構23的隙縫陣列為對準的隙縫陣列所形成的束光闌25，以讓未經偏轉的射束通過。射束24在束光闌25上的此類偏轉可有效將經偏轉的個別射束24“切斷”，即：防止其到達目標，未經偏轉的射束是能夠通過而不受約束且因此不會受到熄滅機構23與束光闌陣列25所遮斷。用於熄滅陣列23的控制訊號是在圖型串流器14中所產生及經送出為電氣訊號15且由調變機構16所轉換成為光學控制訊號。 The beam 22 is projected onto the extinguishing mechanism 23, which in this example includes an array of slots having its deflection mechanism. The extinguishing mechanism 23 is capable of deflecting the individually selected beam 24 to its slot with the extinguishing mechanism 23. The array is a beam stop 25 formed by an aligned array of slits to allow undeflected beams to pass. Such deflection of the beam 24 on the beam stop 25 effectively "cuts" the deflected individual beam 24, ie prevents it from reaching the target, the undeflected beam being able to pass without being constrained and thus It is not blocked by the extinguishing mechanism 23 and the beam stop array 25. The control signal for extinguishing the array 23 is generated in the pattern streamer 14 and sent as an electrical signal 15 and converted by the modulation mechanism 16 into an optical control signal.

光學控制訊號20被送到熄滅陣列23以輸送用於熄滅射束的切換指令。投射器5使未經偏轉的射束22聚焦且將未經偏轉的射束朝寫入方向偏轉在目標9之上，因此實現最終投射。帶電粒子射束22的最終投射到目標9之上致能曝光，而同時將射束22在目標9之上朝第一方向偏轉，而目標9是由目標定位系統9-13朝其橫向於第一方向的第二方向移動。 The optical control signal 20 is sent to the extinguishing array 23 to deliver a switching command for extinguishing the beam. The projector 5 focuses the undeflected beam 22 and deflects the undeflected beam above the target 9 towards the writing direction, thus achieving a final projection. The final projection of the charged particle beam 22 onto the target 9 enables exposure while simultaneously deflecting the beam 22 above the target 9 in a first direction, while the target 9 is oriented laterally by the target positioning system 9-13 The second direction of one direction moves.

圖3示意顯示其可使用在根據本發明之實施例的一種隙縫陣列21中的構件的拓撲配置的俯視圖。該隙縫陣列被分成隙縫區域26與無隙縫區域27。隙縫區域26代表其經配置來接收帶電粒子束的區域且包含通孔之形式的隙縫。除了其他功能以外，無隙縫區域27經配置來提供對於隙縫陣列21之內的構件的支撐。無隙縫區域可經作用分割成二半，各個半部提供作用到相鄰的隙縫區域，如由圖3中的虛線所指出。目標是由在隙縫陣列之下方的射束朝方向S所掃描。通常，隙縫陣列的高度h可為至少26mm，且寬度w可為至少26mm，在此特定實施例中較佳為更大者。將被瞭解的是，在此佈局的變化亦可經使用，舉例來說，隙縫與無隙縫區域不必為等寬，且隙縫與無隙縫區域的方位不必為垂直於掃描方向。隙縫陣列可經納入作為在系統中的第二電極。FIG. 3 schematically shows a top view of a topological configuration of components that can be used in a slot array 21 in accordance with an embodiment of the present invention. The slot array is divided into a slot region 26 and a slotless region 27. The slot region 26 represents a slot that is configured to receive a region of the charged particle beam and that includes a via. The slotless region 27 is configured to provide support for components within the slot array 21, among other functions. The slotless region can be split into two halves by action, with each half providing action to an adjacent slot region, as indicated by the dashed line in FIG. The goal is to scan the beam S below the slot array in the direction S. Generally, the height h of the slot array can be at least 26 mm and the width w can be at least 26 mm, preferably larger in this particular embodiment. It will be appreciated that variations in this layout may also be used, for example, the slits and the non-slit regions need not be of equal width, and the orientation of the slits and the non-slit regions need not be perpendicular to the scanning direction. The slot array can be incorporated as a second electrode in the system.

圖4a示意顯示隙縫陣列之第一實施例的橫截面，特別是在隙縫區域26與無隙縫區域27之間的轉變區域。在此圖中，帶電粒子束的方向與加速電場的方向是由箭頭e所指出。儘管僅有部分的隙縫區域26與無隙縫區域27經顯示，該二個區域是在相同平面延伸，且多個束與無隙縫區域可如在圖3所示而存在。在此實施例中，第二電極包含本體30，其中存在未貫穿孔31，未貫穿孔是等於隙縫36的尺寸。此等未貫穿孔是適用來保存在從隙縫區域到無隙縫區域的轉變上之電場的均勻度。藉由維持該電場的均勻度，帶電粒子束不會正好在從隙縫區域到無隙縫區域之轉變處為經***。Figure 4a schematically shows a cross section of a first embodiment of a slot array, in particular a transition region between the slot region 26 and the gapless region 27. In this figure, the direction of the charged particle beam and the direction of the accelerating electric field are indicated by the arrow e. Although only a portion of the slot region 26 and the slotless region 27 are shown, the two regions extend in the same plane, and the plurality of bundles and the gapless regions may exist as shown in FIG. In this embodiment, the second electrode comprises a body 30 in which there is a non-through hole 31 which is equal to the size of the slit 36. These non-through holes are the uniformity of the electric field that is applied to preserve the transition from the slot region to the slotless region. By maintaining the uniformity of the electric field, the charged particle beam does not split as well at the transition from the slot region to the slotless region.

該電極可在無隙縫的區域(無隙縫區域27)包含支柱32、34。支柱32包含內部導管33，冷卻媒體可透過其流通，其可對於使電極與隙縫陣列冷卻為必要，因此防止崩潰與失效。冷卻液體可藉由泵送或藉由對流而經循環通過導管系統。雖然僅有一個導管被顯示在此圖中，更多者可基於冷卻需求與振動需求而存在於其他的柱中。僅有二個柱被顯示在此圖中，然而可能存在更多者。The electrode can include struts 32, 34 in the region of no gap (no gap region 27). The post 32 includes an internal conduit 33 through which the cooling medium can circulate, which may be necessary to cool the electrode and slot array, thus preventing collapse and failure. The cooling liquid can be circulated through the conduit system by pumping or by convection. Although only one conduit is shown in this figure, more can be present in other columns based on cooling requirements and vibration requirements. Only two columns are shown in this figure, however there may be more.

隙縫區域26包含通孔36或隙縫36，其經配置在隙縫陣列中而用於將帶電粒子束轉換為複數個帶電粒子射束。在一個實施例中，隙縫可具有較小的出口開口35(射束退出隙縫之處)，相較於入口開口(射束進入隙縫之處)。以此方式，隙縫是藉由縮小其通過該隙縫之射束的橫截面而作為限流隙縫。隙縫的此限流性質降低在所造成的複數個帶電粒子射束的像差。The slot region 26 includes a through hole 36 or slot 36 that is configured in the slot array for converting the charged particle beam into a plurality of charged particle beams. In one embodiment, the slot may have a smaller exit opening 35 (where the beam exits the slot) as compared to the inlet opening (where the beam enters the slot). In this way, the slit acts as a restricted flow slit by reducing the cross section of the beam passing through the slit. This current limiting property of the slit reduces the aberration of the resulting plurality of charged particle beams.

圖4b示意顯示隙縫陣列之第二實施例的橫截面，其中該隙縫陣列是有效升高在本體表面之上方。已得知的是，在無隙縫區域27作出一個大的未貫穿孔40，(朝面對源的方向，射束自其到達隙縫陣列)有效將隙縫區域26的上表面升高在無隙縫區域的上表面之上方亦有助維持電場的均勻性。有利的是，此降低無隙縫區域的複雜度，因此使製造容易且降低成本。Figure 4b schematically illustrates a cross section of a second embodiment of a slot array wherein the slot array is effectively raised above the surface of the body. It is known that a large, non-through hole 40 is formed in the gapless region 27 (the beam from which it reaches the slot array in the direction facing the source) effectively raises the upper surface of the slot region 26 in the gapless region. Above the upper surface also helps maintain the uniformity of the electric field. Advantageously, this reduces the complexity of the gapless region, thus making manufacturing easier and reducing costs.

在根據圖4a與4b的實施例中，限流隙縫可經凹陷在其面對源之隙縫區域26的上表面之下方。凹陷部可藉由形成隙縫為具有較大直徑的入口(束進入隙縫之處)與部分沿著隙縫的口徑或在出口(束退出隙縫之處)之較小直徑的限流部分來作成。在圖4a與4b的實施例中，隙縫是藉由在環繞各個隙縫的上表面中具有較大的開口所凹陷，在上表面中形成下陷部，其逐步減小到在下陷部的底部所形成的較小的開口。此造成其經凹陷在隙縫陣列上表面之下方的隙縫的較小出口開口。In the embodiment according to Figures 4a and 4b, the restriction slit can be recessed below its upper surface facing the source slot region 26. The depression can be formed by forming a slit into a larger diameter inlet (where the bundle enters the slit) and a portion of the smaller diameter of the orifice along the orifice or at the outlet (where the bundle exits the slit). In the embodiment of Figures 4a and 4b, the slit is recessed by having a larger opening in the upper surface surrounding each slit, and a depressed portion is formed in the upper surface, which is gradually reduced to the bottom portion of the depressed portion. The smaller opening. This results in a smaller exit opening that is recessed through the slit below the upper surface of the array of slits.

在圖4a與4b中的限流隙縫可經充分凹陷以將隙縫置放在無電場或具有降低電場的高度。在隙縫陣列的上表面所存在的電場將脹大到凹陷部，使得負透鏡是在電場影響下而形成。此可有利為用來將帶電粒子射束投射到第二隙縫陣列上，再次為以限流方式。此第二隙縫陣列可沿著射束的路徑而存在更遠。The restriction slits in Figures 4a and 4b can be sufficiently recessed to place the slits at an electric field free or at a height that reduces the electric field. The electric field present on the upper surface of the slot array will swell to the recess such that the negative lens is formed under the influence of the electric field. This can be advantageously used to project a charged particle beam onto the second slot array, again in a current limiting manner. This second slot array can exist further along the path of the beam.

圖4c示意顯示根據本發明之隙縫的第二實施例的橫截面。僅有一個單獨的隙縫經顯示，然而，根據此實施例的複數個隙縫可存在於隙縫陣列的各個隙縫區域之中。在此實施例中，隙縫的入口36是小於出口35，使得隙縫的最窄部分是在隙縫入口而產生錐狀的孔。以此方式，二次電子的產生被避免，由於帶電粒子束的原始電子不會刮到隙縫的內壁。甚者，任何經產生的二次電子將經歷朝向隙縫的加速場。在隙縫陣列的上表面所存在的電場將再次脹大到凹陷部，如在圖4c所示。藉由尺度的小心選擇，出口35可再次被置放在無電場區域中，如在圖4c所示。雖然僅有一個隙縫是在此顯示，隙縫陣列亦可有利為經升高在表面之上方，如在圖4a與4b所示。Figure 4c shows schematically a cross section of a second embodiment of a slit according to the invention. Only a single slit is shown, however, a plurality of slits in accordance with this embodiment may be present in each of the slot regions of the slot array. In this embodiment, the inlet 36 of the slot is smaller than the outlet 35 such that the narrowest portion of the slot is a tapered opening at the slot entrance. In this way, the generation of secondary electrons is avoided because the original electrons of the charged particle beam do not scratch the inner wall of the slit. Moreover, any secondary electrons produced will experience an acceleration field towards the slot. The electric field present on the upper surface of the slot array will again swell to the recess as shown in Figure 4c. With careful selection of dimensions, the outlet 35 can again be placed in the no-electric field, as shown in Figure 4c. Although only one slit is shown here, the slot array can also be advantageously raised above the surface as shown in Figures 4a and 4b.

圖5示意顯示根據本發明之收斂機構的一個實施例，其包含作用為第一與第二電極的第一與第二隙縫陣列、以及三個附加電極。第一電極48包含單一個平板電極且第二電極49是再次被包括為隙縫陣列。Figure 5 shows schematically an embodiment of a convergence mechanism according to the invention comprising first and second slot arrays acting as first and second electrodes, and three additional electrodes. The first electrode 48 comprises a single plate electrode and the second electrode 49 is again included as an array of slits.

第一與第二電極48、49經配置使得電場為存在其間。根據用於使目標曝光所需者為何，此場可為加速場(相對於帶電粒子源，實際為帶電粒子源的陰極)或減速場。The first and second electrodes 48, 49 are configured such that an electric field is present therebetween. Depending on the person required to expose the target, this field can be an acceleration field (actually a cathode of a charged particle source relative to a charged particle source) or a deceleration field.

加速場可藉由關於帶電粒子源將第一電極設定在電壓V(例如：4 kV)且將第二電極設定在較高電壓Va(例如：5 kV)來達成。其他電壓亦可經使用且達成相同效應。以此方式為有利的是，可能藉由將導線置放在帶電粒子束中且在該導線上具有電場端而實際將電流添加到帶電粒子束，因此修改電場的形狀。在此創新方式中，較佳許多的像差降低可經達成，相較於否則由電極電壓V與Va以及電極幾何性(諸如：其間距、直徑與厚度)之僅有調整所將為可能者。第一電極的電位可經調整，俾使由於帶電粒子束在第二電極上的衝擊所產生的二次電子經歷朝向第二電極的加速場，因此降低二次電子的折回散射。該三個附加電極經配置為所謂的聚焦鏡組，其用於使發散的帶電粒子束為準直。該聚焦鏡組包含三個透鏡元件，即：設定在電壓V1的上方透鏡板45、設定在電壓V2的中間透鏡板46、與設定在電壓V3的下方透鏡板47。為了透鏡要具有準直效應，對於具有諸如電子的帶負電粒子之束而言，V2應為高於V1與V3。舉例來說，關於帶電粒子源，V2可經設定在20 kV且V1、V3可經設定在5 kV。其他電壓亦可經使用且達成類似效應。The acceleration field can be achieved by setting the first electrode at a voltage V (eg, 4 kV) with respect to the charged particle source and setting the second electrode at a higher voltage Va (eg, 5 kV). Other voltages can also be used and achieve the same effect. In this way it is advantageous to actually add a current to the charged particle beam by placing the wire in a charged particle beam and having an electric field end on the wire, thus modifying the shape of the electric field. In this innovative approach, a much better reduction in aberrations can be achieved, as compared to otherwise only adjustments by electrode voltages V and Va and electrode geometry (such as pitch, diameter and thickness). . The potential of the first electrode can be adjusted such that the secondary electrons generated by the impact of the charged particle beam on the second electrode undergo an acceleration field toward the second electrode, thereby reducing the backscattering of the secondary electrons. The three additional electrodes are configured as so-called focusing mirrors for collimating the diverging charged particle beam. The focusing lens group includes three lens elements, that is, an upper lens plate 45 set at a voltage V1, an intermediate lens plate 46 set at a voltage V2, and a lower lens plate 47 set at a voltage V3. In order for the lens to have a collimating effect, for a bundle with negatively charged particles such as electrons, V2 should be higher than V1 and V3. For example, with respect to a charged particle source, V2 can be set at 20 kV and V1, V3 can be set at 5 kV. Other voltages can also be used and achieve similar effects.

在操作期間，帶電粒子源52產生發散的帶電粒子束51。當發散的帶電粒子束通過三個附加電極45、46、47，該束被準直化且通過第一與第二電極48、49。最後，第二電極49作用來將帶電粒子束51分成複數個帶電粒子射束50，如在圖5所示意顯示。During operation, charged particle source 52 produces a diverging charged particle beam 51. When the diverging charged particle beam passes through three additional electrodes 45, 46, 47, the beam is collimated and passes through the first and second electrodes 48, 49. Finally, the second electrode 49 acts to divide the charged particle beam 51 into a plurality of charged particle beams 50, as shown schematically in FIG.

在此實施例中，該等電極可針對其面對帶電粒子束的邊緣而具有磨圓的邊緣。藉由將該等邊緣磨圓，尖銳邊緣經避免，顯著降低由於高電場所引起從該等邊緣之放電的可能性。典型而言，該等邊緣是被彎曲為在面對帶電粒子束的邊緣具有在30與70 mm之間的曲率半徑。In this embodiment, the electrodes may have rounded edges for their facing edges of the charged particle beam. By rounding the edges, the sharp edges are avoided, significantly reducing the likelihood of discharge from the edges due to the high electrical location. Typically, the edges are curved to have a radius of curvature between 30 and 70 mm at the edge facing the charged particle beam.

概括而言，該等電極的填充因數是傾向為相當低，即：帶電粒子束的橫截面的面積是比該束通過在電極中的開口的面積為較小許多。然而，低的填充因數是在收斂機構之最小尺寸上加諸不想要的限制，要求收斂機構為大於可能期望者。舉例來說，投射系統的所需焦距限制了帶電粒子光學系統的可用高度。較大的收斂機構造成較長的帶電粒子光學系統與較長的焦距，其增加在帶電粒子與相同電荷之間的不想要交互作用。此外，帶電粒子源可能未置放在該等電極的電場內而位在離該等電極的某個距離處。增大從源到該等電極的距離可能造成帶電粒子束的亮度減小，且可能提高在帶電粒子間的庫侖交互作用。實際上，在帶電粒子源與第二電極之間的距離可為少於或等於300 mm而電極的孔徑可為多於或等於40 mm。為了克服此等問題，在一個實施例中，填充因數是相當高，實際為50%或更大。In summary, the fill factor of the electrodes is tend to be rather low, i.e., the area of the cross section of the charged particle beam is much smaller than the area of the beam passing through the opening in the electrode. However, a low fill factor imposes an undesirable limit on the minimum size of the convergence mechanism, requiring that the convergence mechanism be greater than might be expected. For example, the desired focal length of the projection system limits the available height of the charged particle optical system. The larger convergence mechanism results in a longer charged particle optical system with a longer focal length which increases the unwanted interaction between charged particles and the same charge. In addition, charged particle sources may not be placed within the electric field of the electrodes and at some distance from the electrodes. Increasing the distance from the source to the electrodes may result in a decrease in the brightness of the charged particle beam and may increase the Coulomb interaction between the charged particles. In practice, the distance between the charged particle source and the second electrode can be less than or equal to 300 mm and the pore size of the electrode can be more than or equal to 40 mm. To overcome these problems, in one embodiment, the fill factor is quite high, actually 50% or greater.

為了系統的適當操作，必要的是，所有構件是經對準達到高準確度。此可藉由將該等電極整合為單一個單元、將個別的構件以機械式對準且確保熱干擾致使該等構件為關於光軸而同等膨脹來達成。For proper operation of the system, it is necessary that all components are aligned to achieve high accuracy. This can be achieved by integrating the electrodes into a single unit, mechanically aligning the individual components, and ensuring that thermal interference causes the members to expand equally about the optical axis.

圖6(非依比例)示意顯示以隙縫陣列之形式的第二電極49之彎曲表面的一個實施例。在圖6所示的實施例中，隙縫陣列的上表面是以簡單凸狀(朝源的方向)朝上彎曲來形成圓頂狀部分。曲面的中心可比彎曲截面的邊緣為高3 mm，曲面具有例如50 mm的周長。在此圖中，帶電粒子束的方向與加速電場的方向是由箭頭e所指出。隙縫區域54代表其經配置來接收帶電粒子束的區域且各個區域54包含通孔之形式的複數個隙縫。無隙縫區域55是無隙縫的區域。Figure 6 (not to scale) schematically illustrates one embodiment of a curved surface of the second electrode 49 in the form of a slot array. In the embodiment shown in Fig. 6, the upper surface of the slot array is curved upward in a simple convex shape (direction toward the source) to form a dome-shaped portion. The center of the surface can be 3 mm higher than the edge of the curved section, and the surface has a circumference of, for example, 50 mm. In this figure, the direction of the charged particle beam and the direction of the accelerating electric field are indicated by the arrow e. The slit region 54 represents a region thereof configured to receive a charged particle beam and each region 54 includes a plurality of slits in the form of through holes. The gapless region 55 is a region free of slits.

在另一個實施例中，隙縫陣列的上表面是根據置中在環繞系統光軸的餘弦函數所朝上彎曲。得知的是，此餘弦形狀提供更佳的像差降低。In another embodiment, the upper surface of the array of slits is curved upwardly according to a cosine function centered on the optical axis of the surrounding system. It is known that this cosine shape provides better aberration reduction.

在此等實施例中，彎曲表面的半徑是大於帶電粒子束在該束與隙縫陣列表面相交處的直徑。In such embodiments, the radius of the curved surface is greater than the diameter of the charged particle beam at the intersection of the beam and the surface of the slot array.

在此等實施例中，隙縫陣列可經細分成為其含有用於帶電粒子射束之通孔的區域、與無隙縫的區域，如上所述。加速電場是存在於另一個電極與第二電極之間，第二電極可經設定在例如5 kV的電壓Va。In such embodiments, the slot array can be subdivided into regions containing vias for charged particle beams, and regions without gaps, as described above. The accelerating electric field is present between the other electrode and the second electrode, and the second electrode can be set to a voltage Va of, for example, 5 kV.

第一電極與經包括作為隙縫陣列的彎曲的第二電極是一起作用來顯著降低在帶電粒子系統中的像差。以此方式，較佳許多的像差降低可經達成，相較於否則由電壓與幾何性之僅有調整所將為可能者。第二電極的彎曲表面是使源自聚焦鏡組之電場的電場線成形。The first electrode acts in conjunction with the curved second electrode included as an array of slits to significantly reduce aberrations in the charged particle system. In this way, a much better aberration reduction can be achieved, as would otherwise be possible with only adjustments in voltage and geometry. The curved surface of the second electrode is shaped to shape the electric field lines originating from the electric field of the focusing mirror.

圖7(再次為非依比例)示意顯示收斂機構的另一個實施例，其為以不同於圖5之實施例的佈局。在此圖中，相同的部分是如同在圖5來標號。操作與優點是可比得上如在圖5所示的實施例。在此實施例中，第一電極48如前所述經包括作為單一個平板電極，且第二電極53再次經包括作為隙縫陣列而現為置放在第一電極的前方，較為接近源。電場是存在於第一與第二電極之間。根據所需要者為何，此場可為加速或減速場。第一電極的電位可經調整，俾使由於在第二電極上的衝擊所產生的二次電子經歷朝向第二電極的加速場，因此將二次電子保留在其中。Figure 7 (again, not to scale) schematically illustrates another embodiment of a convergence mechanism that is a different layout than the embodiment of Figure 5. In this figure, the same parts are labeled as in Fig. 5. The operation and advantages are comparable to the embodiment as shown in FIG. In this embodiment, the first electrode 48 is included as a single plate electrode as previously described, and the second electrode 53 is again included as a slot array and is now placed in front of the first electrode, closer to the source. An electric field is present between the first and second electrodes. This field can be an acceleration or deceleration field depending on what is needed. The potential of the first electrode can be adjusted such that the secondary electrons generated by the impact on the second electrode undergo an acceleration field toward the second electrode, thereby retaining the secondary electrons therein.

該三個附加電極是再次經配置為所謂的聚焦鏡組，其用於使發散的帶電粒子束為準直。該聚焦鏡組包含三個透鏡元件，即：設定在電壓V1的上方透鏡板45、設定在電壓V2的中間透鏡板46、與設定在電壓V3的下方透鏡板47。為了透鏡要具有準直效應，V2應為高於V1與V3。舉例來說，關於帶電粒子源，V2可經設定在20 kV且V1、V3可經設定在5 kV。其他電壓亦可經使用且達成相同效應。The three additional electrodes are again configured as so-called focusing mirrors for collimating the diverging charged particle beam. The focusing lens group includes three lens elements, that is, an upper lens plate 45 set at a voltage V1, an intermediate lens plate 46 set at a voltage V2, and a lower lens plate 47 set at a voltage V3. In order for the lens to have a collimating effect, V2 should be higher than V1 and V3. For example, with respect to a charged particle source, V2 can be set at 20 kV and V1, V3 can be set at 5 kV. Other voltages can also be used and achieve the same effect.

再者，在操作期間，帶電粒子源52產生發散的帶電粒子束51。Again, during operation, the charged particle source 52 produces a diverging charged particle beam 51.

當發散的帶電粒子束通過三個附加電極，該束被準直化且通過第二電極且然後通過第一電極。第二電極53作用來將帶電粒子束51分成複數個帶電粒子射束50，如在圖8所示意顯示。When the diverging charged particle beam passes through three additional electrodes, the beam is collimated and passes through the second electrode and then through the first electrode. The second electrode 53 acts to divide the charged particle beam 51 into a plurality of charged particle beams 50, as shown schematically in FIG.

圖8示意顯示如在圖7之實施例所包括的第二電極的一個實施例。Figure 8 shows schematically an embodiment of a second electrode as embodied in the embodiment of Figure 7.

在此實施例中，第二電極隙縫陣列的上表面是以簡單凸狀(朝離開源的方向)朝下彎曲來形成凹陷部。再者，電極的彎曲表面是使源自聚焦鏡組之電場的電場線成形。曲面的中心可比彎曲截面的邊緣為深3 mm，曲面具有例如50 mm的直徑。在此圖中，帶電粒子束的方向與加速電場的方向是由箭頭e所指出，然而，減速場亦可經應用。隙縫區域54代表其經配置來接收帶電粒子束的區域且各個區域54包含以通孔之形式的隙縫。無隙縫區域55是無隙縫的區域。In this embodiment, the upper surface of the second electrode slot array is curved downward in a simple convex shape (toward the direction away from the source) to form a depressed portion. Furthermore, the curved surface of the electrode is formed by shaping the electric field lines originating from the electric field of the focusing mirror. The center of the surface may be 3 mm deeper than the edge of the curved section, and the surface has a diameter of, for example, 50 mm. In this figure, the direction of the charged particle beam and the direction of the accelerating electric field are indicated by the arrow e, however, the deceleration field can also be applied. The slot region 54 represents a region that is configured to receive a beam of charged particles and each region 54 includes a slot in the form of a through hole. The gapless region 55 is a region free of slits.

在另一個實施例中，隙縫陣列的上表面是根據置中在環繞系統光軸的餘弦函數所朝下彎曲。得知的是，此餘弦形狀提供更佳的像差降低。In another embodiment, the upper surface of the array of slits is curved downwardly according to a cosine function centered on the optical axis of the surrounding system. It is known that this cosine shape provides better aberration reduction.

在此等實施例中，隙縫陣列可仍細分成為其含有用於帶電粒子射束之通孔的區域、與無隙縫的區域，如上所述。In such embodiments, the slot array can still be subdivided into regions containing vias for charged particle beams, and regions without gaps, as described above.

圖9示意顯示收斂機構的又一個實施例的橫截面，該收斂機構包含以第一電極57之形式的單一個電極準直器與以第二電極58之形式的隙縫陣列。帶電粒子源56在操作期間發出帶電粒子束(未顯示)。Figure 9 shows schematically a cross section of yet another embodiment of a convergence mechanism comprising a single electrode collimator in the form of a first electrode 57 and a slot array in the form of a second electrode 58. Charged particle source 56 emits a charged particle beam (not shown) during operation.

第一電極57是在較低的電位，且第二電極58是在較高的電位。結果，加速場是存在於第一電極57與第二電極58之間。在一個實施例中，在第一與第二電極之間的加速電場是例如藉由關於帶電粒子源(尤其是帶電粒子源的陰極)將第一電極設定在4.5 kV到5.5 kV之範圍中的電位V且將第二電極設定在15 kV到30 kV之範圍中的電位Va來達成。The first electrode 57 is at a lower potential and the second electrode 58 is at a higher potential. As a result, the acceleration field exists between the first electrode 57 and the second electrode 58. In one embodiment, the accelerating electric field between the first and second electrodes is such that the first electrode is set in the range of 4.5 kV to 5.5 kV by, for example, a charged particle source (especially a cathode of a charged particle source). The potential V is set by setting the second electrode to a potential Va in the range of 15 kV to 30 kV.

在第一與第二電極之間的電場是俾使發散的帶電粒子束收斂，在此實施例中，使得帶電粒子束成為實質平行。帶電粒子束接著撞擊在第二電極58。因為第二電極58採取隙縫陣列之形式，該束被轉換成為複數個帶電粒子射束。除了阻隔一部分的束之外，第二電極58亦有效止住電場。The electric field between the first and second electrodes is such that the diverging charged particle beam converges, in this embodiment, the charged particle beam is made substantially parallel. The charged particle beam then impinges on the second electrode 58. Because the second electrode 58 takes the form of a slot array, the beam is converted into a plurality of charged particle beams. In addition to blocking a portion of the beam, the second electrode 58 also effectively stops the electric field.

在此實施例中，第一電極採取一種形式，其中包含其具有源面對側與非源面對側的第一部分與其具有源面對側與非源面對側的第二部分。第一部分可具有在其非源面對側的第一橫截面，而第二部分可具有在其非源面對側的第二橫截面。第二橫截面的平均直徑可為大於第一橫截面的平均直徑。In this embodiment, the first electrode takes the form of a first portion having a source facing side and a non-source facing side and a second portion having a source facing side and a non-source facing side. The first portion may have a first cross section on its non-source facing side and the second portion may have a second cross section on its non-source facing side. The average diameter of the second cross section may be greater than the average diameter of the first cross section.

較佳而言，第一部分的高度是大於第二部分的高度。該等部分可具有磨圓的凸輪廓之實質圓形的形狀，即：鐘狀的形狀。單元件準直透鏡有效使得發散的電子束折射，尤其是在加速場的存在時。此類的加速場可藉由使用第二電極58來產生。第二電極58採取隙縫陣列的形式，即：具有複數個隙縫的平板，致使複數個射束能夠產生。Preferably, the height of the first portion is greater than the height of the second portion. The portions may have a substantially circular shape with a rounded convex profile, i.e., a bell-like shape. A single element collimating lens is effective to refract the diverging electron beam, especially in the presence of an accelerating field. Such an accelerating field can be generated by using the second electrode 58. The second electrode 58 takes the form of an array of slits, i.e., a plate having a plurality of slits, such that a plurality of beams can be produced.

在一個實施例中，第一與第二部分是使用磨圓的接頭來接合，降低在帶電粒子束中所引入的像差。已得知的是，根據此實施例之一種電極可使用極板材料來容易且經濟地生產。In one embodiment, the first and second portions are joined using a rounded joint to reduce aberrations introduced in the charged particle beam. It has been known that an electrode according to this embodiment can be easily and economically produced using a plate material.

本發明已經關於上文所論述的某些實施例來描述。將被承認的是，在沒有脫離本發明的精神與範疇之情況下，此等實施例是容許對於熟習此技術人士為眾所週知的種種修改與替代形式。是以，雖然特定實施例已經描述，此等者僅為舉例且並未限制本發明的範疇，其為在隨附的申請專利範圍中所定義。The present invention has been described in relation to certain embodiments discussed above. It will be appreciated that such embodiments are susceptible to various modifications and alternative forms that are well known to those skilled in the art without departing from the spirit and scope of the invention. It is to be understood that the specific embodiments have been described by way of example only and are not intended to limit the scope of the invention, which is defined in the scope of the appended claims.

1．．．帶電粒子系統1. . . Charged particle system

2‧‧‧控制系統 2‧‧‧Control system

3‧‧‧真空室 3‧‧‧vacuum room

4‧‧‧帶電粒子柱 4‧‧‧Charged particle column

5‧‧‧投射器 5‧‧‧Projector

6‧‧‧計量框架 6‧‧Measurement framework

7‧‧‧振動隔離器 7‧‧‧Vibration isolator

8‧‧‧底座 8‧‧‧Base

9‧‧‧目標 9‧‧‧ Target

10‧‧‧晶圓台 10‧‧‧ Wafer

11‧‧‧測量系統 11‧‧‧Measurement system

12‧‧‧夾頭 12‧‧‧ chuck

13‧‧‧長衝程驅動器 13‧‧‧Long-stroke drive

14‧‧‧圖型串流器 14‧‧‧Graphic streamer

15‧‧‧電氣訊號 15‧‧‧Electric signal

16‧‧‧調變機構 16‧‧‧Transformation agency

17‧‧‧帶電粒子源 17‧‧‧Powered particle source

18‧‧‧帶電粒子束 18‧‧‧Charged particle beam

19‧‧‧準直透鏡 19‧‧‧ Collimating lens

20‧‧‧光學控制訊號 20‧‧‧ Optical control signals

21‧‧‧隙縫陣列 21‧‧‧ slit array

22‧‧‧射束 22‧‧‧ Beam

23‧‧‧熄滅機構 23‧‧‧ extinguishing mechanism

24‧‧‧偏轉的射束 24‧‧‧ deflected beam

25‧‧‧束光闌陣列 25‧‧‧beam array

26‧‧‧隙縫區域 26‧‧‧ slit area

27‧‧‧無隙縫區域 27‧‧‧No gap area

30‧‧‧本體 30‧‧‧Ontology

31‧‧‧未貫穿孔 31‧‧‧not through holes

32‧‧‧支柱 32‧‧‧ pillar

33‧‧‧內部導管 33‧‧‧Internal catheter

34‧‧‧支柱 34‧‧‧ pillar

35‧‧‧隙縫的出口 35‧‧‧The exit of the slot

36‧‧‧隙縫的入口 36‧‧‧ Entrance to the gap

40‧‧‧未貫穿孔 40‧‧‧not through holes

45‧‧‧上方透鏡板 45‧‧‧Upper lens plate

46‧‧‧中間透鏡板 46‧‧‧Intermediate lens plate

47‧‧‧下方透鏡板 47‧‧‧Lower lens plate

48‧‧‧第一電極 48‧‧‧First electrode

49‧‧‧第二電極 49‧‧‧second electrode

50‧‧‧帶電粒子射束 50‧‧‧Charged particle beam

51‧‧‧帶電粒子束 51‧‧‧Charged particle beam

52‧‧‧帶電粒子源 52‧‧‧Powered particle source

53‧‧‧第二電極 53‧‧‧second electrode

54‧‧‧隙縫區域 54‧‧‧ slit area

55‧‧‧無隙縫區域 55‧‧‧No gap area

56‧‧‧帶電粒子源 56‧‧‧Powered particle source

57‧‧‧第一電極 57‧‧‧First electrode

58‧‧‧第二電極58‧‧‧second electrode

本發明的特徵與優點是參考以下圖式來理解，其中：The features and advantages of the present invention are understood by reference to the following drawings, in which:

圖1示意顯示一種已知的帶電粒子微影系統，其包括晶圓台構件；Figure 1 shows schematically a known charged particle lithography system comprising a wafer table member;

圖2詳細顯示已知技術帶電粒子曝光系統的電子光柱的示意代表圖；Figure 2 shows in detail a schematic representation of an electron beam of a known charged particle exposure system;

圖3顯示第二電極的示意俯視圖，其顯示交替的束與無隙縫區域；Figure 3 shows a schematic top view of a second electrode showing alternating beam and gapless regions;

圖4a示意顯示第二電極的橫截面，第二電極包含根據本發明之一種隙縫陣列元件，其包括根據本發明之隙縫的第一實施例；Figure 4a shows schematically a cross section of a second electrode comprising a slit array element according to the invention comprising a first embodiment of a slit according to the invention;

圖4b示意顯示根據本發明之隙縫的第二實施例；Figure 4b schematically shows a second embodiment of a slit according to the invention;

圖4c示意顯示隙縫陣列的第二實施例，其包括自本體所升高者；Figure 4c schematically shows a second embodiment of a slot array comprising a person raised from the body;

圖5示意顯示根據本發明之收斂機構的一個實施例，其使用三個附加電極；Figure 5 shows schematically an embodiment of a convergence mechanism according to the invention using three additional electrodes;

圖6示意顯示隙縫陣列之彎曲表面的一個實施例；Figure 6 is a schematic illustration of one embodiment of a curved surface of a slot array;

圖7示意顯示根據本發明之收斂機構的另一個實施例，其使用三個附加電極；Figure 7 shows schematically another embodiment of a convergence mechanism according to the invention using three additional electrodes;

圖8示意顯示隙縫陣列之彎曲表面的另一個實施例；且Figure 8 is a schematic illustration of another embodiment of a curved surface of a slot array;

圖9示意顯示收斂機構的另一個實施例，其包含單一個電極。Figure 9 shows schematically another embodiment of a convergence mechanism comprising a single electrode.

45．．．上方透鏡板45. . . Upper lens plate

46．．．中間透鏡板46. . . Intermediate lens plate

47．．．下方透鏡板47. . . Lower lens plate

48．．．第一電極48. . . First electrode

49．．．第二電極49. . . Second electrode

50．．．帶電粒子射束50. . . Charged particle beam

51．．．帶電粒子束51. . . Charged particle beam

52．．．帶電粒子源52. . . Charged particle source

Claims

一種帶電粒子微影系統，其用於將圖型轉移到諸如晶圓的目標表面上，該種系統包含：帶電粒子源，其適用於產生發散的帶電粒子束；收斂機構，其用於使該發散的帶電粒子束折射，該收斂機構包含第一電極；及隙縫陣列元件，其包含複數個隙縫，該隙縫陣列元件形成第二電極，其中該第二電極經配置來將該帶電粒子束分成複數個帶電粒子射束；其中該種系統是適用於在該第一電極與該第二電極之間建立電場，其中該第二電極的隙縫陣列被細分成為交替的無隙縫區域與複數個隙縫為存在其處的區域，及其中該等無隙縫區域是備有用於冷卻媒體的導管。 A charged particle lithography system for transferring a pattern onto a target surface, such as a wafer, the system comprising: a charged particle source adapted to generate a diverging charged particle beam; a convergence mechanism for a diverging charged particle beam refraction, the convergence mechanism comprising a first electrode; and a slit array element comprising a plurality of slits, the slit array element forming a second electrode, wherein the second electrode is configured to divide the charged particle beam into a plurality a charged particle beam; wherein the system is adapted to establish an electric field between the first electrode and the second electrode, wherein the slit array of the second electrode is subdivided into alternating gapless regions and a plurality of slits exist The area there, and the non-slit areas therein, are provided with conduits for the cooling medium.

如申請專利範圍第1項之系統，其中該電場是加速電場。 A system as claimed in claim 1, wherein the electric field is an accelerating electric field.

如申請專利範圍第2項之系統，其中該加速電場是藉由將該第一電極以關於該第二電極的相對較低電位來通電所建立。 The system of claim 2, wherein the accelerating electric field is established by energizing the first electrode at a relatively lower potential with respect to the second electrode.

如申請專利範圍第1項之系統，其中該等無隙縫區域是備有一或多個未貫穿孔。 The system of claim 1, wherein the non-slit regions are provided with one or more non-through holes.

如申請專利範圍第1項之系統，其中該隙縫陣列具有面對該帶電粒子源的上表面，且其中在該等隙縫區域中的上表面具有經升高在該等無隙縫區域中的上表面之上方的高度。 The system of claim 1, wherein the slot array has an upper surface facing the source of charged particles, and wherein an upper surface in the slot region has an upper surface raised in the non-slit region Above height.

如申請專利範圍第1項之系統，其中該隙縫陣列的隙縫具有經凹陷在面對該帶電粒子源的上表面之下方的最窄部分。 The system of claim 1, wherein the slit of the slit array has a narrowest portion recessed below the upper surface facing the source of charged particles.

如申請專利範圍第6項之系統，其中該等隙縫的最窄部分經凹陷到無該電場的高度。 A system as in claim 6 wherein the narrowest portion of the slit is recessed to a height free of the electric field.

如申請專利範圍第7項之系統，其中在操作中，該系統是在該等隙縫具有凹陷的最窄部分之位置處形成負靜電透鏡。 A system according to claim 7 wherein, in operation, the system forms a negative electrostatic lens at a location where the slits have a narrowest portion of the depression.

如申請專利範圍第1項之系統，其中該第一電極的填充因數是大於50%。 The system of claim 1, wherein the first electrode has a fill factor greater than 50%.

如申請專利範圍第1項之系統，其中在該第二電極中的隙縫的填充因數是大於50%。 The system of claim 1, wherein the fill factor in the second electrode is greater than 50%.

如申請專利範圍第1項之系統，其中該收斂機構更包含適以形成聚焦鏡組(Einzel lens)的至少三個附加電極。 The system of claim 1, wherein the converging mechanism further comprises at least three additional electrodes adapted to form an Einzel lens.

如申請專利範圍第1項之系統，其中該等隙縫具有在面對該源之側的第一直徑d1以及在面對該目標之側的第二直徑d2，且其中d1是小於d2。 The system of claim 1, wherein the slit has a first diameter d1 on a side facing the source and a second diameter d2 on a side facing the target, and wherein d1 is less than d2.

一種隙縫陣列元件，其用在帶電粒子微影系統中，且包含複數個隙縫，該隙縫陣列元件被細分成為交替的無隙縫區域與該複數個隙縫為存在其處的區域，其中該等無隙縫區域是備有用於冷卻媒體的導管。 A slit array element for use in a charged particle lithography system and comprising a plurality of slits, the slit array elements being subdivided into alternating gapless regions and the plurality of slits being regions present therein, wherein the gapless slits The area is equipped with a conduit for cooling the media.

如申請專利範圍第13項之隙縫陣列元件，其中該等無隙縫區域是備有一或多個未貫穿孔。 The slit array element of claim 13, wherein the non-slit region is provided with one or more non-through holes.

如申請專利範圍第13項之隙縫陣列元件，其中該隙縫陣列的隙縫具有經凹陷在該上表面之下方的最窄部分。 A slot array element according to claim 13 wherein the slot of the slot array has a narrowest portion recessed below the upper surface.

如申請專利範圍第13項之隙縫陣列元件，其中該等隙縫具有在面對該源之側的第一直徑d1以及在面對該目標之側的第二直徑d2，且其中d1是小於d2。 The slit array element of claim 13, wherein the slit has a first diameter d1 on a side facing the source and a second diameter d2 on a side facing the target, and wherein d1 is less than d2.

一種帶電粒子束產生器，其包含：帶電粒子源，其適用於產生發散的帶電粒子束；收斂機構，其用於使該發散的帶電粒子束折射，該收斂機構包含第一電極；及如申請專利範圍第13至16項中任一項之隙縫陣列元件，該隙縫陣列元件形成第二電極；其中該種系統是適用於在該第一電極與第二電極之間建立電場，其中該第二電極的隙縫陣列被細分成為交替的無隙縫區域與複數個隙縫為存在其處的區域，其中該等無隙縫區域是備有用於冷卻媒體的導管。 A charged particle beam generator comprising: a charged particle source adapted to generate a diverging charged particle beam; a convergence mechanism for refracting the diverging charged particle beam, the convergence mechanism comprising a first electrode; and applying The slot array element of any one of clauses 13 to 16, wherein the slot array element forms a second electrode; wherein the system is adapted to establish an electric field between the first electrode and the second electrode, wherein the second The slot array of electrodes is subdivided into alternating non-slot regions and a plurality of slots are regions present therein, wherein the non-slot regions are provided with conduits for cooling media.

如申請專利範圍第17項之束產生器，其中該電場是加速電場。 A beam generator as claimed in claim 17, wherein the electric field is an accelerating electric field.

如申請專利範圍第18項之束產生器，其中該加速電場是藉由將該第一電極以關於該第二電極的相對較低電位來通電所建立。 A beam generator as in claim 18, wherein the accelerating electric field is established by energizing the first electrode at a relatively lower potential with respect to the second electrode.

如申請專利範圍第17項之束產生器，其中該隙縫陣列的隙縫具有經凹陷在面對該帶電粒子源的隙縫陣列上表面之下方的最窄部分，且其中該等隙縫的最窄部分經凹陷到無該電場的高度。 A beam generator according to claim 17, wherein the slit of the slit array has a narrowest portion recessed below the upper surface of the slit array facing the charged particle source, and wherein the narrowest portion of the slit is Depression To the height without the electric field.

如申請專利範圍第20項之束產生器，其中在操作中，該束產生器是在該等隙縫具有凹陷的最窄部分之位置處形成負靜電透鏡。 A beam generator according to claim 20, wherein in operation, the beam generator forms a negative electrostatic lens at a position where the slits have the narrowest portion of the depression.

如申請專利範圍第17項之束產生器，其中該第一電極的填充因數是大於50%。 The beam generator of claim 17, wherein the first electrode has a fill factor of greater than 50%.

如申請專利範圍第17項之束產生器，其中在該第二電極中的隙縫的填充因數是大於50%。 The beam generator of claim 17, wherein the fill factor in the second electrode is greater than 50%.

如申請專利範圍第17項之束產生器，其中該收斂機構更包含適以形成聚焦鏡組的至少三個附加電極。 The beam generator of claim 17, wherein the convergence mechanism further comprises at least three additional electrodes adapted to form a focusing mirror.

如申請專利範圍第24項之束產生器，其中該等電極中的一或多者具有面對該帶電粒子束的曲面，其具有在30與70mm之間的曲率半徑。 A beam generator according to claim 24, wherein one or more of the electrodes have a curved surface facing the charged particle beam having a radius of curvature between 30 and 70 mm.

如申請專利範圍第17項之束產生器，其中該收斂機構是以單一元件準直透鏡之形式的第一電極所組成。 A beam generator according to clause 17 of the patent application, wherein the convergence mechanism is composed of a first electrode in the form of a single element collimating lens.

一種使發散的帶電粒子束折射之方法，該種方法包含：藉由帶電粒子源來提供發散的帶電粒子束；藉由收斂機構來使該發散的帶電粒子束折射，該收斂機構包含第一電極與第二電極，該第二電極採取隙縫陣列的形式；在該第一電極與第二電極之間形成加速電場；且從經折射的帶電粒子束來產生複數個實質平行的帶電粒子射束，其中該第二電極的隙縫陣列被細分成為交替的無隙縫區域與複數個隙縫為存在其處的區域，其中該等無隙縫區域是備有用於冷卻媒體的導管。 A method of refracting a diverging charged particle beam, the method comprising: providing a diverging charged particle beam by a charged particle source; refracting the diverging charged particle beam by a convergence mechanism, the convergence mechanism comprising a first electrode And a second electrode, the second electrode is in the form of an array of slits; an accelerating electric field is formed between the first electrode and the second electrode; and a plurality of substantially parallel charged particle beams are generated from the refracted charged particle beam, Wherein the slot array of the second electrode is subdivided into alternating non-slit regions and a plurality of slots are regions present therein, wherein the non-slot regions are provided with conduits for cooling media.

如申請專利範圍第27項之方法，其中該形成加速電場的步驟包含將該第一電極以相較於該第二電極的相對較低電位來通電。The method of claim 27, wherein the step of forming an accelerating electric field comprises energizing the first electrode at a relatively lower potential than the second electrode.